Dynamics-based articulation angle estimator for a vehicle combination

1. A system for estimating an articulation angle of a vehicle combination, the system comprising:

a motion sensor for sensing one or more linear and/or angular motion quantities of the vehicle combination;

a dynamics-based estimator configured to

estimate state variables including the articulation angle on the basis of the sensed motion quantities, wherein the dynamics-based estimator is dependent on one or more masses and moments of inertia of the vehicle combination; and

provide vehicle control information based on the estimated state variables to a vehicle controller.

2. The system of claim 1 , wherein the dynamics-based estimator is a Kalman filter.

3. The system of claim 1 , wherein the sensed linear and angular motion quantities include one or more of:

a longitudinal velocity of a first vehicle unit,

a longitudinal velocity of a second vehicle unit,

a lateral velocity of the first vehicle unit,

a lateral velocity of the second vehicle unit,

a yaw rate of the first vehicle unit, and

a yaw rate of the second vehicle unit.

4. The system of claim 1 , wherein the sensed linear and angular motion quantities do not include a steering angle.

5. The system of claim 1 , further comprising:

a kinematics-based estimator configured to estimate state variables including the articulation angle on the basis of the sensed motion quantities, wherein the kinematics-based estimator is independent of the masses and the moments of inertia of the vehicle combination.

6. The system of claim 1 , further comprising:

an articulation angle sensor.

7. The system of claim 5 , further comprising:

a selector configured to output one of:

an estimate by the dynamics-based estimator,

an estimate by the kinematics-based estimator,

a measurement of the articulation angle, and

a value obtained by merging one or more of the above.

8. The system of claim 7 , wherein the selector includes a machine-learning model.

9. The system of claim 7 , wherein the selector is further configured to indicate a quality or confidence level of its output.

10. The system of claim 1 , wherein the vehicle combination is not an articulated steering vehicle (ASV).

11. A method of estimating an articulation angle of a vehicle combination, comprising:

determining values based on the vehicle combination of one or more masses and moments of inertia;

defining a dynamics-based model of the vehicle combination on the basis of the determined values;

repeatedly sensing one or more linear and/or angular motion quantities of the vehicle combination and feeding these to the model;

extracting an estimate of the articulation angle from a current state of the model; and

providing vehicle control information based on the estimate of the articulation angle to a vehicle controller.

12. A computer program comprising a non-transitory computer readable medium having stored thereon instructions which, when the program is executed by a computer, cause the computer to:

determine values based on the vehicle combination of one or more masses and moments of inertia;

define a dynamics-based model of the vehicle combination on the basis of the determined values;

repeatedly sense one or more linear and/or angular motion quantities of the vehicle combination and feeding these to the model;

extract an estimate of the articulation angle from a current state of the model; and

providing vehicle control information based on the estimate state of the articulation angle to a vehicle controller.